York Air Cooled Screw Liquid Chillers (Style G)

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Operation and Maintenance Manual

Text of York Air Cooled Screw Liquid Chillers (Style G)

FORM 201.19-EG4 (903)

Better ecology, Better economy.

Air Cooled Screw Liquid Chillers(STYLE G)

28971AR

50 200 Tons

R-407C Optimized80 400 Tons 280 kW 1400 kW 60 Hz

200, 230,380, 460, AND 575

TABLE OF CONTENTSIntroduction........................................................................................................ 3 Specifications .................................................................................................... 4 Accessories and Options................................................................................... 8 Temperatures and Flows .................................................................................. 11 Water Pressure Drop .........................................................................................12 Ratings ..............................................................................................................16 Physical Data.....................................................................................................34 Dimensions........................................................................................................38 Operating Weights (Aluminum Fin Coils) .......................................................... 82 Isolator Selection (Aluminum Fin Coils).............................................................83 Operating Weights ............................................................................................85 Isolator Selection ..............................................................................................86 Isolator Selection ..............................................................................................89 Isolator Details...................................................................................................92 Electrical Data ...................................................................................................94 Electrical Notes..................................................................................................105 Power Connection Options................................................................................106 Typical Control Wiring........................................................................................110 Application Data ................................................................................................112 Guide Specifications.......................................................................................... ...........................................................................................................................

NOMENCLATUREYC YORK Chiller YC = YORK Chiller Air-Cooled Compressor Type S = Screw Nominal Capacity (tons) Unit Designator E = High Efficiency 2 A S 0208 E B 46 Y G Design Series Type Start Y = Star (WYE)-Delta X = Across-the-Line Voltage Code 17 = 200-3-60 28 = 230-3-60 40 = 380-3-60 46 = 460-3-60 58 = 575-3-60 Refrigerant B = R-407C

YORK INTERNATIONAL

IntroductionYORK Air Cooled Screw Liquid Chillers R-407C Optimized

FORM 201.19-EG4

28971AR

The YORK eco2 technology takes the YCAS Air Cooled Screw Chillers yet another step beyond the competition. Using unique (patent pending) heat transfer design, the eco2 chillers exploit the special glide characteristic of HFC refrigerant R-407C, resulting in excellent performance from a machine using a zero ozone depletion refrigerant. These Air Cooled Screw Compressor machines are the state-of-theart in air cooled chillers, providing chilled fluids for all air conditioning applications. Completely self-contained and designed for outdoor installation, they employ low noise, energy efficient, serviceable, semi-hermetic screw compressors designed and manufactured specifically for this new product line. These compressors, with reliable twin-screw technology, are ideally matched to evaporators and condensers optimally configured for superior heat transfer and unit efficiency. Condenser coils are arranged to maximize air flow using full airfoil, high efficiency, low noise fans driven by low energy motors. The screw compressors, high efficiency evaporator, enhanced heat transfer condensers, and weather tight power and microprocessor control centers are mounted on a bolted, fully galvanized and powder painted, all steel base, for unsurpassed reliability and performance.YORK INTERNATIONAL

3

SpecificationsThese YORK air cooled chillers are shipped as a complete factory package. Each unit is completely assembled with all interconnecting refrigerant piping and internal wiring, ready for field installation, including: HFC REFRIGERANT R-407C: R-407C has outstanding properties which make it the superior HFC refrigerant for air cooled chillers. R-407C is an HFC (hydrofluorocarbon). HFCs have zero ODP (ozone depletion potential) because they contain no chlorine to damage the ozone layer. R-407C achieves low total global warming impact in YORKs eco2 air cooled chillers. Direct effect GWP (Global Warming Potential) assumes refrigerant is allowed to leak into the atmosphere. Refrigerants suitable for air cooled chillers have similar GWPs, and the slight differences are not significant when evaluating TEWI (Total Equivalent Warming Impact). Instead, the CO2 and rejection heat from utilities generating electricity to run the machines account for 98% to 99% of TEWI over the typical life of a chiller. Therefore, the critical issue is energy efficiency. The YORK eco2 air cooled chillers have excellent energy efficiency. R-407C is safe and chemically stable. R-407C is listed in ASHRAE Standard-34 Number Designation and Safety Classification for Refrigerants as an A-1 refrigerant; lowest toxicity, non-flammable. R-407C is similar to R-22. Though there are many refrigerants, HFC R-407C retains many of the fine properties of HCFC R-22, the venerable work-horse refrigerant of air-cooled DX chillers for decades, but with no chlorine. In fact, the pressures, temperatures, and heat transfer characteristics of R-407C are so similar to R-22, it has been applied for years as a drop-in alternative in machines originally designed for R-22. R-407C has Glide, which benefits performance. Glide describes the property of a refrigerant boiling across a temperature range at a given pressure (it is zeotropic), rather than at a single temperature (azeotropic). R407C is a blend of three constituents (23% R-32, 25% R-125, and 52% R-134a) and is zeotropic. At typical water chiller evaporator pressures, R-407C has about 8F (4.4C) of glide. While placing a refrigerant with glide into a machine designed for an azeotropic refrigerant (no glide, like R-22) typically diminishes chiller performance, the YORK eco2 machine exploits glide to achieve exceptional energy efficiency. R-407C is a good DX refrigerant, well suited to air cooled chillers. DX, or Direct Expansion (refrigerant evaporated in the tubes, and water flowing over the tubes inside the shell), and Flooded (refrigerant boiling in a pool in the shell, and water inside the tubes) are terms used to describe typical chiller evaporator 4 heat exchangers. While flooded designs are easily employed on indoor equipment, DX is preferred on air-cooled equipment for better refrigerant and oil management across the broad range of ambient conditions, resulting in greater application flexibility and system reliability. EVAPORATOR: YORKs special eco2 Counter-Flow heat exchanger design takes advantage of the Glide characteristic intrinsic to HFC R-407C. It employs technologically advanced (patented) high efficiency tube assemblies which make possible a single refrigerant pass, DX type cooler that is better than a flooded cooler; delivering refrigerant suction gas warmer than the leaving chilled water at full load. Independent circuits provided for each compressor. Design working pressure of the shell waterside is 150 PSIG (10.3 Bar), and 350 PSIG (23.8 Bar) for the refrigerant side. Constructed and tested in accordance with applicable sections of ASME Pressure Vessel13.0 11.0

Temperature F

9.0 7.0 5.0 3.0 1.0

Wat er

HFC-4

07C

Water In Refrigerant Out

Code, Section VIII, Division (1). Water side exempt per paragraph U-1, (c), (6). Water baffles fabricated from galvanized steel to resist corrosion. Removable heads allow access to internally-enhanced, seamless, copper tubes. Water vent and drain connections included. Cooler equipped with thermostat controlled heater for protection to -20F (-29C) ambient, and insulated with 3/4" (19 mm) flexible, closed-cell foam (k = 0.25). SEMI-HERMETIC YORK SCREW COMPRESSORS: Continuous function, microprocessor controlled, 3-way proportional Capacity Control Valve provides regulated output pressure independent of valve input pressure for a stable, smooth, and precise match of compressor capacity to cooling load to 10% of chillerYORK INTERNATIONAL

Water Out Refrigerant InLD04906

FORM 201.19-EG4

capacity. Automatic spring return of capacity control valve to minimum load position ensures compressor starting at minimum motor load. Internal discharge check to prevent rotor backspin upon shut-down. Acoustically Tuned, internal discharge gas muffler eliminates objectionable noise at the source, while optimizing flow for maximum performance. Reliable suction gas cooled, high efficiency, accessible hermetic motor with APT2000 type magnet wire and redundant overload protection using both thermistor and current overload protection. Suction gas screen and serviceable, 0.5 micron full flow oil filter within the compressor housing. Cast iron compressor housing precisely machined for optimal clearances and superb efficiency. Entire compressor, from suction to discharge has a Design Working Pressure of 450 PSIG (31 Bar). 350W compressor body cartridge heater.

resistant system. Liquid